1. Field of the Disclosure
This invention relates to floor panels.
More particularly, this invention relates to floor panels of the type which is at least composed of a substrate and a top layer provided on this substrate, wherein said top layer comprises a print. As known, above such motif a transparent or translucent synthetic material layer may be provided, which then forms part of said top layer.
In particular, the present invention relates to panels of the type which, at two or more opposite edges, comprises coupling means or coupling parts, with which two of such floor panels can be coupled at the respective edges, such that they are locked to each other in a horizontal direction perpendicular to the respective edge and as in the plane of the floor panels, as well as in a vertical direction perpendicular to the plane of the floor panels. Such floor panels can be applied for composing a so-called floating floor covering, wherein the floor panels are connected to each other at their edges, however, lie freely on the underlying surface.
2. Related Art
From WO 97/47834, laminate floor panels are known for forming a floating floor covering. However, laminate floor panels have the disadvantage that they mostly are provided with a moisture-sensitive substrate, namely, MDF or HDF (Medium Density Fiberboard or High Density Fiberboard), and that the top layer provided on this substrate, when the floor covering is in use, leads to the occurrence of ticking noises. The top layer, to wit, is composed of thermo-hardening resin and leads to the development of a very hard surface layer. The substrate, too, is hard due to the high density of MDF or HDF. On average, laminate floor panels have a thickness situated between 6 and 12 millimeters, wherein the thickness of the top layer mostly is less than 0.5 millimeters.
From EP 1 938 963 and WO 2010/023042, vinyl-based floor panels are known for forming such floating floor covering. Such vinyl-based floor panels mostly have a thickness of 3 to 5 millimeters and have a high material density. Above the print, a transparent thermoplastic layer and possibly a superficial lacquer layer are provided. The thermoplastic layer mostly has a thickness of 1 millimeter or more. Such layer, on the one hand, provides wear resistance to the floor panel, and, on the other hand, allows forming a relief on the surface. So, for example, a chamfer can be realized in this transparent layer, such as in the aforementioned WO 2010/023042, or impressions for imitating wood pores can be provided. Nevertheless, the floor panels of the state of the art still do give a plastic-like impression. The thick thermoplastic layer may lead to a reduced view on the print, by a lack of transparency. Inherent to these floor panels is also their limited bending stiffness and their high deformability. These features lead to problems when the floor panels are provided on an uneven underlying surface. Namely, after a certain period of time, the unevennesses of the underlying surface may migrate towards the surface of the floor covering. With a local load, for example, underneath the legs of tables or chairs, permanent impressions will be created, which also are undesired.
From WO 2007/081267 and US 2004/146695, floor panels are known with a substrate and a top layer provided thereon, wherein the top layer is composed of a print and a thick and soft transparent layer situated above this print. At one edge, the floor panel has a lowered edge region in the form of a groove with a horizontal bottom. Possibly, the bottom of this groove can extend on a level situated below the global level of the print. Possibly, the bottom of the groove can be performed colored. This technique is suitable for imitating cement joints or other tile joints, however, leaves much to be desired when it should be applied with floor panels representing a print with a wood pattern.
Floor panels with a relatively thick soft top layer, for example, a thermoplastic top layer, further have the disadvantage that they can be pushed upward at the edge, for example, in that the floor panels are tensioned against each other or in that, when the floor covering is being walked on, a frictional contact is created between the shoe and the edge of the top layer. This may result in an accelerated wear on these edges and/or to possibly unsafe situations. Up to now, it was thought that a thick transparent top layer was necessary for withstanding such wear.